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This paper is focused on a new copper-nickel thick film resistive paste which was designed and experimentally developed for the realization of low-ohmic power resistors. This copper-nickel paste has been designed for use in combination with thick printed copper conductors and in comparison with conventional ruthenium-based thick film resistor pastes allows firing in a nitrogen protective atmosphere. The copper-nickel paste was prepared from copper and nickel microparticles, glass binder particles and a combination of organic solvents optimized for its firing in a nitrogen atmosphere. This paper covers a detailed description of copper-nickel paste composition and its thermal properties verified by simultaneous thermal analysis, a description of the morphology of dried and fired copper-nickel films, as well as the electrical parameters of the final printed resistors. It has been proven by electron microscopy with element distribution analysis that copper and nickel microparticles diffused together during firing and created homogenous copper-nickel alloy film. This film shows a low temperature coefficient of resistance 45 x 0-6 K-1 and low sheet resistance value 45 mW/square. It was verified that formulated copper-nickel paste is nitrogen-fireable and well-compatible with thick printed copper pastes. This combination allows the realization of power substrates with directly integrated low-ohmic resistors. This paper is focused on a new copper-nickel thick film resistive paste which was designed and experimentally developed for the realization of low-ohmic power resistors. This copper-nickel paste has been designed for use in combination with thick printed copper conductors and in comparison with conventional ruthenium-based thick film resistor pastes allows firing in a nitrogen protective atmosphere. The copper-nickel paste was prepared from copper and nickel microparticles, glass binder particles and a combination of organic solvents optimized for its firing in a nitrogen atmosphere. This paper covers a detailed description of copper-nickel paste composition and its thermal properties verified by simultaneous thermal analysis, a description of the morphology of dried and fired copper-nickel films, as well as the electrical parameters of the final printed resistors. It has been proven by electron microscopy with element distribution analysis that copper and nickel microparticles diffused together during firing and created homogenous copper-nickel alloy film. This film shows a low temperature coefficient of resistance 45 x 0-6 K-1 and low sheet resistance value 45 mW/square. It was verified that formulated copper-nickel paste is nitrogen-fireable and well-compatible with thick printed copper pastes. This combination allows the realization of power substrates with directly integrated low-ohmic resistors.

Detection of nitrite-ion has become very important for various industrial fields due to its wide application range such as food additives and a rust preventive agent for steels. In this study, we attempted at developing an advanced method to produce layered perovskite-type cuprates based thick-film device for highly sensitive electrochemical sensor for nitrite-ion with a capacity of wide concentration range. Here, layered perovskite-type oxide powders could be synthesized by a polymer precursor method which was deposited on alumina supports with gold electrode by an electrophoretic deposition method. The sensor performance was measured by an amperometric method for nitrite-ion detection. It was found that the Gd2CuO4-based electrode showed fast and good linear responses to nitrite-ion for a wide range of concentration., 第57回セラミックス基礎科学討論会, 2019年1月16日～17日, 仙台国際センター, 宮城, 日本

To clearly show how important the impact of side chains on organic solar cells (OSCs) is, we designed three acceptors IDIC-CxPh (x = 4, 5, or 6) via subtle side-chain regulation. Despite this small change, significant distinctions were detected. IDIC-C4Ph devices achieve an optimal efficiency of 13.94% under thermal annealing, but thermal-assistant solvent-vapor annealing hugely suppresses the efficiencies to 10%. However, the C6Ph side chain endows extremely disordered stacking orientations, generating moderate efficiencies of ~12.50%. Excitingly, the IDIC-C5Ph affords an unexpected two-channel π-π charge transport (TCCT) property, boosting the fill factor (FF) by up to 80.02% and efficiency to 14.56%, ranking the best among five-ring fused-ladder-type acceptors. Impressively, the special TCCT behavior of IDIC-C5Ph enables 470 nm thick-film OSC with a high FF of up to 70.12% and efficiency of 13.01%, demonstrating the great promise in fabricating large-scale OSCs., Graphical abstract, Public summary • OSCs are a promising technology to transform the solar energy to electricity • This article reports an efficient TCCT photovoltaic material through subtle side-chain modification • The TCCT property enables 13% efficiency with FF reaching 70% in 470 nm thick-film photovoltaics

[EN] This paper compares the simulated performance of three different screen-printed probe geometries for Electro-chemical Impedance Spectroscopy probes for use in harsh environments. The best performing probe, which is equipped with guarding electrodes that are proven to help with the electric field uniformity, shows a linear response with the medium's resistivity using a 1 kHz sinusoidal input current with a sensitivity of 0.163 mV/Omega m in the range of 2.5 Omega m to 50 Omega m in a medium with relative permittivity of 20. Additionally, the phase shift shows a linear relationship to the medium's relative permittivity and a sensitivity of 0.1 degrees/epsilon(r) in the range of 5-81 using a 1 MHz sinusoidal input current. The equivalent circuitmodels of the probes were constructed and the values of the components have been reported. The best performing probe was fabricated and experimentally tested to back up the theoretical simulations and proposed models. The experimental and simulated values are within a +/- 6% error margin., This work was supported by the University of Cyprus Internal Funds (Post-Doctoral Researchers-Advanced Level, Article 102).

The theory of cyclic voltammetry of ion transfer-electron transfer coupled reactions in a thick organic film modified electrode is developed. The model system consists of a planar electrode completely covered by an organic phase, which in turn is in contact with an aqueous phase, each containing a supporting electrolyte. It is shown that the coupling between the ion transfer-electron transfer processes at both, solid∣liquid and liquid∣liquid interfaces, has a marked effect on the shape of the voltammogram. The model allows the analysis of the system in different experimental conditions. In particular, the results for different concentration ratios of the redox probe and supporting electrolytes are presented. The variation of the potential of the solid∣liquid and the liquid∣liquid interfaces reflects changes in concentration of the species involved. This variation is presented as a descriptor of the shape of the voltammograms. The theoretical results are contrasted with experimental behaviour reported in literature. Fil: Zanotto, Franco Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Fernández, Ricardo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Dassie, Sergio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina

Reproducibility of the sensor response is one of the fundamental themes for obtaining marketable devices with a high degree of reliability. This parameter becomes decisive especially if the sensor signals are used to identify compound mixtures by means of recognition algorithms. In fact, to apply the same algorithm to different devices, sensors must be identical within a minimum error margin. This point became crucial for medical diagnostic tools, e.g., for cancer screening and monitoring. A set of three thermo-activated thick-film Zinc Oxide (ZnO) sensors, obtained from the same screen-printing deposition, have been tested in laboratory with diverse gases and two biological fecal samples. Fecal samples have been employed in the clinical validation protocol of a device for non-invasive colorectal cancer pre-screening, as emitters of oncologic volatile biomarkers. Sensors showed a good reproducibility degree, with an error lower than 10% of response value for all compounds, reaching 1%–2% for some gases.

Concrete carbonation is one of the main triggers of the corrosion process and hence of the premature deterioration of concrete reinforcements. In order to monitor and control the carbonation process, a potentiometric sensor using thick-film technology was developed. This paper includes the results of the research carried out to characterise the pH sensor, including the materials, response time, sensitivity, detection limit, reproducibility, reversibility and the study of chloride interference. The sensors have been studied in pore solutions and concrete specimens. The study shows that the thick-film sensor has a potentiometric response to variations in pH and is capable of providing continuous, real-time information on the progress of the carbonation front., The pre-doctoral scholarship was granted to Roman Bataller Prats by the Research Staff Training Program, "Formacion de Personal Investigador (FPI) 2012" from Universitat Politecnica de Valencia and to Jose Enrique Ramon Zamora by the University Faculty Training Program FPU13/0091, "Formacion del Profesorado Universitario (FPU) 2013" from the Spanish Ministry of Science and Innovation. The financial support from the Spanish Government and the European FEDER funds MAT2012-38429-004-04. ETSIE (UPV) by their support to the laboratory is also gratefully acknowledged.

Electrochemical behavior of SiO electrode as a Na-ion battery anode was investigated by using thick-film electrodes without any binder or conductive additive. The SiO electrode reacted with Na to exhibit a reversible capacity of over 200 mA h g−1 at the first cycle, whereas Si electrode showed less capacity. We previously demonstrated that SiO being an amorphous material is composed of three-dimensional SiO4 tetrahedral network similar to silica glass and Si clusters, and that the Si clusters are finely dispersed in the SiO4 matrices. Given this characteristics, it is considered that the capacity obtained from the SiO originates from an alloying reaction of the Si clusters having a high surface energy with Na.

This contribution presents the integration of glass-ceramic tapes on alumina substrates to increase the sensitivity of thermoelectric hydrocarbon gas sensors. Both ceramic materials have different thermal conductivity. Their combination into one sensor structure significantly improves the sensitivity by at the same time maintaining the excellent mechanical stability at high temperatures. Furthermore, this special technology allows for an easy integration of additional functional elements such as screen-printed thermocouples for temperature control purposes.

Studies on electromigration phenomenon in thick-film structures on alumina and LTCC substrates are presented in this paper. The effects of storage of Au and Ag electrode patterns in temperature range up to 300 °C under voltage bias were examined. The leakage characteristics of electrodes with 100 μm spacing at 50 V dc bias as a function of time and temperature are presented and analyzed. Scanning electron microscope (SEM) equipped with the energy-dispersive X-ray spectroscopy (EDX) detector was applied for determination of metal ions transport. Test structures with Au-based conductive material are much more resistant to electromigration than Ag-based layers.

Free-standing electroded piezoelectric PZT thick-lms are straightforward fabricatedthanks to the association of the low-cost screen-printing technology with the sacricial layermethod. Au/PZT/Au bridges are directly attached onto the alumina substrate on top of it theyare processed. In addition, completely released disks are also processed. A study of the behaviourof these components shows the inuence of both the releasing process and the densicationon the piezoelectric properties of the PZT layer. From the electromechanical measurements,electroded PZT cantilevers and disks are promising for actuator, sensor or SHM applications.

Supervision of systems and devices has become more and more important with regard to maintenance requirements and quality management. To achieve these monitoring requirements many different kinds of sensors are needed. At the Fraunhofer IFAM different sensor types have been developed on the basis of thick-film technology and especially by screen-printing. The development of sensor structures spread over a wide field of measurement categories like temperature, humidity, forces, rotational speed or positioning. Here the focus is on thermocouples and magnetic sensor structures for rotational speed and position measurements. Investigations on the functionality of the sensor structures have been performed like correspondence of electrical properties with literature values, comparisons in performance in relation to conventionally produced sensors.

This work aims at a broad overview of the results obtained with metal-sulfide materials in the field of chemoresistive gas sensing. Indeed, despite the well-known electrical, optical, structural and morphological features previously described in the literature, metal sulfides present lack of investigation for gas sensing applications, a field in which the metal oxides still maintain a leading role owing to their high sensitivity, low cost, small dimensions and simple integration, in spite of the wide assortment of sensing materials. However, despite their great advantages, metal oxides have shown significant drawbacks, which have led to the search for new materials for gas sensing devices. In this work, Cadmium Sulfide and Tin (IV) Sulfide were investigated as functional materials for thick-film chemoresistive gas-sensors fabrication and they were tested both in thermo- and in photo-activation modes. Furthermore, electrical characterization was carried out in order to verify their gas sensing properties and material stability, by comparing the results obtained with metal sulfides to those obtained by using their metal-oxides counterparts. The results highlighted the possibility to use metal sulfides as a novel class of sensing materials, owing to their selectivity to specific compounds, stability, and the possibility to operate at room temperature.

In order to monitor the chloride penetration processes, a potentiometric embedded thick-film sensor was developed. This paper includes the results of research on the characterization of Cl− sensors made of Ag/AgCl resistive pastes (materials, sensitivity and detection limit, reproducibility, reversibility and response time, long-term performance and reliability in the presence of interfering agents). Theoretical expressions have been developed to describe the potentiometric response including the presence of OH− and bromide ions. The study shows that thick-film sensors are able to monitor Cl− activity as a function of the redox potential. Sensors are also capable of providing reliable and continuous real-time information on phenomena related to the progress of the chloride penetration front in concrete specimens. These sensors are a promising tool because thick-film technology allows us to obtain miniaturized, low-cost, robust and stable long-term sensors for Cl− monitoring., The pre-doctoral scholarship granted to Roman Bataller Prats within the program "Formacion de Personal Investigador (FPI) 2012" from Universitat Politecnica de Valencia is gratefully acknowledged.

A thick-film electrochemical sensor with an iridium-carbon working electrode was used for determining polyphenols and their antioxidant capacity in white wine. Caffeic acid was used as a model species because it has the ability to produce the highest oxidation current. The correlation coefficient of 0.9975 was obtained between sensor response and caffeic acid content. The total phenolic content (TPC) and scavenging activity on 1,1-diphenyl-2-pycrylhydrazyl (DPPH·) radical were also found to be strongly correlated with the concentration of caffeic acid, with a correlation coefficient of 0.9823 and 0.9958, respectively. The sensor prototype was proven to be a simple, efficient and cost effective device to evaluate the antioxidant capacity of substances.

A three-electrode based CO(2) sensor was fabricated using thick-film technology. The performance of this sensor was further enhanced by incorporating platinum nanoparticles onto the working electrode surface. An eight-fold increase in the signal output was obtained from the electrode with the platinum nanoparticles. The sensing output was linearly related to the CO(2) presented. Stability measurements demonstrated that the decline of the active surface area and the sensitivity of the sensor were 8% and 13%, respectively, over a two week period of time. The sensor response appeared to be a structural dependence of the crystallographic orientation of platinum electrode.

A complete six degree of freedom (6 DOF) force/torque sensor has been designed and fabricated, adapted to wrist rehabilitation applications, with the focus laid on simple, straightforward manufacturing processes. This paper details the mechanical design, 3D modeling, manufacture and characterisation of the sensor. Compared to previous work [1], this design has the advantage of simple, fully planar machining, and the load-sensing elements all lie on the same plane, making the device compatible with single-film deposition or a foil bonding process. The sensor was machined from steel, and the piezoresistive load-sensing bridges were deposited using thick-film technology. We used commercial thick-film materials in the work described here. A new lead-free materials system compatible with low processing temperatures (

[ES] Los objetivos del presente proyecto son los siguientes: -Estudiar, construir y caracterizar un electrodo de referencia estándar, en concreto el electrodo Ag/AgCl, por tecnología thick-film. Para ello deberemos analizar: -Los distintos tipos de pastas cerámicas que hemos usado para la deposición, así como las distintas temperaturas de trabajo a las que han sido sometidas, con la finalidad de esclarecer las mejores condiciones para el buen funcionamiento de este tipo de sensor químico. -Los efectos que tienen los cloruros, como interferente, en la medida del potencial, ya que pretendemos obtener un electrodo cuya concentración de cloruros sea independiente de la concentración de cloruros del medio a estudiar. (Si la concentración de cloruros no varía, el potencial de Ag/AgCl tampoco, por lo tanto el electrodo que hemos desarrollado se podrá considerar electrodo de referencia)

Thick-film screen printed silver–silver chloride (Ag/AgCl) reference electrodes have been fabricated and investigated as an alternative to liquid electrolyte Ag/AgCl reference electrodes. The performance of the electrodes was examined with variations of the potassium chloride (KCl) concentration in the final (top) layer of the electrode. Also, different types of binder (glass and polymer) were tested for the underlying Ag/AgCl layer. The addition of another layer on top of the KCl containing salt matrix layer has been found to provide a better stability in varying concentrations of KCl test solutions. The electrodes were found to give a satisfactory performance when tested for stability in different pH solutions., The authors wish to thank the UK Environment Agency and the National Environmental Research Council for partially funding this work.

We present a mechanical model of a triaxial micro accelerometer design using PZT thick-film as the sensing material. The model is based on the full anisotropic material tensors and Eulers' beam equation using simplifying assumptions where the smaller stress contributions are ignored. The model results in design equations that are useful for optimization of the sensitivity and bandwidth and for matching the sensitivity in the three orthogonal directions. A finite-element method (FEM) model is used to verify the analytical model. Equal sensitivity in all three geometrical directions is preferred, which induces a number of limitations in design parameter space, this is used in a design strategy for setting the six independent dimensions of the accelerometer. Design methods for optimum sensitivity of each axis and for equal sensitivity between different axes have been proposed.

It is well known that the dielectric matrix of air-fireable thick film resistors (TFRs) presently used in hybrid microelectronics and passive components invariably consists of a high-lead silicate glass. However, the current trend in the electronic industry is to restrict and eliminate the hazardous elements viz. lead, cadmium etc. from electronic components. An attempt to develop suitable RuO2-based or pyrochlore ruthenate based Pb–Cd free TFRs has been only partially successful till now. We report here the preliminary results of a study aimed to investigate the feasibility of CaRuO3 perovskite-based lead-free TFRs. Our results showed that sheet resistances higher than 1 kΩ/sq. can be easily achieved in a controlled way, with hot and cold temperature coefficients of resistance (TCR) in the range of 325–580 ppm/°C and 180–500 ppm/°C, respectively. Similarly, the compositions also exhibit negligible piezoresistive effects with gauge factor, GFb1. Additionally, the resistors do not exhibit negative structural features, like bleeding or devitrification of glass, observed in previous attempts to develop reliable lead-free TFRs. © 2006 Elsevier B.V. All rights reserved.

The ionophore 1,4,7,10,13-penta(n-octyl)-1,4,7,10,13-pentaazacyclopentadecane (L1) was used for the development of miniaturised perchlorate-selective electrodes in thick-film technology. Different PVC membranes containing L1 and the plasticizers o-nitrophenyl octyl ether (NPOE), dibutyl phthalate (DBP), bis(2-ethylhexyl)sebacate (DOS) and dibutyl sebacate (DBS) were prepared and placed on a graphite working electrode manufactured by using thick film serigraphic technology. The perchlorate selective electrode containing DBS as plasticizer showed a potentiometric Nernstian response of -57 mV per decade in a range of perchlorate concentration from 1 × 10-4 to 1 × 10-1 M with a detection limit of 5 × 10-5 M. The ion selective electrodes containing DBP and NPOE as plasticizers exhibit a working range from 6.3 × 10-5 to 1 × 10-1 M and 7.4 × 10-5 to 1 × 10-1 M for perchlorate, respectively, with a detection limit of ca. 2.2 × 10-5 M. For all three electrodes a response time of ca. 5 s was found. The prepared electrodes do not show appreciable decay of the slope for at least 25 days. Potentiometric selectivity coefficients (log KpotClO4-,X-) with respect to the primary anion perchlorate were evaluated using the fixed interference method. These coefficients are of the order of 10-1.7 or smaller, indicating the relatively poor interference of the different anions studied.

High gas sensitivity, expected when using the unusual longitudinal vibration mode of PZT cantilever for such application, is based on its higher resonant frequency when compared to transversal bending mode. For this purpose, a new PZT cantilever structure has been fabricated with thick-film technology based on the sacrificial layer method. This structure is well adapted to generate the 31’s longitudinal vibration. Studies of the composition and microstructure of Au/PZT/Au beam show the harmlessness of the process. Advantage of the 31’s longitudinal mode for gas detection is confirmed by the values of resonant frequency and good quality factor for a 8×2×0.08 mm3 PZT based cantilever. Indeed, taking a 0.1Hz frequency resolution for the second 31 mode, the limit of detection of 6 ppm toluene is reached with a 44μm PEUT coating.

The integration of a mass detection system in an existing miniaturized differential scanning calorimeter device (DSC-MD) is shown in this study. With a size of only 11 mm x 40 mm x 1.3 mm, the DSC-MD exhibits a thermal resolution, which is comparable to conventional apparatuses. To allow for the determination of mass specific thermal properties, the integration of a mass sensing system based on screen-printed strain gauges onto the device was the focus of this work. By FEM-analysis, the device was simulated, the ideal positions of the strain gauges were identified, and the sensitivity of the mass sensing system was estimated. First tests show promising results in the range of 8 – 200 mg.

The influence of temperature distribution on the melting process in a ceramic differential scanning micro-calorimeter (MC-DSC) is shown. The MC-DSC chip is manufactured in low temperature co-fired ceramics technology (LTCC) as a three-dimensional device that includes all functions of a conventional DSC device. This study deals with the simulation-based optimization of the heater geometry for the second MC-DSC-chip generation to improve both sensitivity and selectivity. The influence of the heater geometry improvement was evaluated by simulation of the melting process of indium. The results suggest both higher sensitivities and higher selectivities.

We investigate in this work the formulation of composite resistive pastes based on epoxy resins and graphite for micro-heater manufacturing via thick-film technology. The resistive paste is first screen-printed onto a printed circuit board (PCB) substrate, and then coated with expandable polydimethylsiloxane (PDMS), a composite based on an elastomeric matrix and expandable microspheres, resulting into one-shot thermal actuators allowing pumping and sealing in microfluidic devices. The resistive paste must therefore have controlled properties, such as rheology, resistivity and temperature stability. This paper details the formulation and characterization of suitable epoxy-graphite resistive composites, and the control of their properties through additives.